1. Field of the Invention
The invention relates to electronic devices used to charge and communicate with mobile electronic devices.
2. Description of the Related Art
In modern society we are becoming ever more mobile. It is very common to have notebook computers in small and light form factors to greatly aid in communications and computing in varying locations. One common aspect of notebook computers is that they are battery powered. As a result, they all have some sort of algorithm to conserve the battery power. Typically this includes entering low-power or standby states after determined periods of inactivity. During these standby or low-power states one of the common things that is done is to turn off power to all of the peripheral devices and peripheral ports.
Also common in the modern mobile society are small electronic mobile devices such as cell phones, music players and PDAs (Personal Data Assistants). All of these are very small, battery powered personal devices. In many cases they connect to a larger computer, such as a notebook computer or a desktop computer, to receive files and to otherwise interface with the larger computer system. Because they are smaller devices and battery powered, they have a limited lifetime on their battery charge. To this end they need to be charged on a reasonably frequent basis.
One of the common ways that has been developed for these types of devices to be recharged is to plug them into the computer using their data connection and then use the power provided on that data connection to recharge the devices. For example, say the device connects by a USB or 1394 interface. A constant DC voltage is provided on each of those interfaces and this DC voltage can be readily used to recharge the batteries in the mobile device. In this manner the user does not have to carry around AC adapters for each of the particular devices and does not have to rely on disposable batteries. They can just use their standard data connection cable for recharging capabilities. This recharging of these small mobile devices is not an appreciable draw or drain on the notebook computer battery, for example, as that is a very high capacity battery as compared to the particular small devices.
Given that this capability of charging the small mobile devices from the larger mobile device such as the notebook computer is common and becoming ubiquitous, it is desirable to be able to make this process as efficient as possible to simplify user operations.